Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

More than 42 percent of those surveyed at 40 colleges said they had felt down, depressed or hopeless several days during the past two weeks, and 13 percent showed signs of being at risk for at least mild depression, based on the students' answers to a series of questions that medical practitioners use to diagnose depressive illness.

Eighty five percent of those surveyed reported feeling stressed in their daily lives in recent months, found the poll of 2,240 undergraduate students ages 18-24 at four-year colleges.

Many of those coping with feeling depressed complained of trouble sleeping, having little energy or feeling down or hopeless — and most hadn't gotten professional help. Eleven percent had had thoughts that they'd be better off dead or about hurting themselves.

That's not just a case of the blues to be shrugged off by taking a break with Facebook or going for a workout.

Kristin Potts, who graduated from Penn State last week with a 4.0 in chemistry and will go on for a master's, says she's seen warning signs among fellow classmates.

"I had a couple friends who didn't come out of their rooms very much," she said. "I tried my hardest not to be like that, but I definitely saw it."

'There's still a stigma'At the University of Maryland in College Park, students were sobered by two suicides within two weeks this past semester.

"It was pretty scary," says Aimee Mayer, a junior studying psychology. She says there's lots of information and help available for students with mental disorders, but "there's still a stigma associated with mental health issues and so a lot of people don't want to go to those services. They feel like they're less cool or something like that if they go. It's like a sign of vulnerability."

Megan Salame, a sophomore studying civil engineering at George Mason University in Fairfax, Va., says she'd turn first to her parents if she felt depressed. But she hastened to add, "Depressed — I don't really like to use that word because it sounds so negative."

Mental health disorders like depression typically begin relatively early in life, doctors say, and college is a natural time for symptoms to emerge.

The AP-mtvU poll exploring the students' state of mind and the pressures they face, including strains from the tough economy. Among the poll results:

Nine percent of students were at risk of moderate to severe depression. That's in line with a recent medical study that found 7 percent of young people had depression.

Almost a quarter of those with a parent who had lost a job during the school year showed signs of at least mild depression, more than twice the percentage of those who hadn't had a parent lose a job. More than twice as many students whose parents had lost a job said they had seriously considered ending their own life, 13 percent to 5 percent.

Among those who reported serious symptoms of moderate depression or worse, just over a quarter had ever been diagnosed with a mental health condition.

More than half of those who reported having seriously considered suicide at some point in the previous year had not received any treatment or counseling.

Just a third of those with moderate symptoms of depression or worse had received any support or treatment from a counselor or mental health professional since starting college.

Nearly half of those diagnosed with at least moderate symptoms weren't familiar with counseling resources on campus.

Anne Marie Albano, an associate professor of clinical psychology at Columbia University, said college is a "tender age" developmentally, a period when young adults start taking responsibility for their lives. They're selecting careers, moving toward financial independence, establishing long-term relationships, perhaps marrying, having children.

The most troubling thing coming out of the AP-mtvU poll and other studies of young adults dealing with depression, she said, is that "they don't get help" at a time when they're just venturing off on their own.

"They have to learn to become their own monitors about their mental health and yet they have no training to do that," she said.

Everyday blues or clinical depression?Alison Malmon, whose older brother, Brian, committed suicide when she was a freshman at the University of Pennsylvania in 2000, decided to do something about it. After searching unsuccessfully for a group that she could bring to campus that would encourage students to talk about mental health issues and seek help, Malmon created Open Minds. That group has grown into the nonprofit Active Minds, with chapters on more than more than 200 campuses.

Malmon, 27, executive director of the nonprofit, says students don't have to worry about how to draw the line between everyday blues and clinical depression.

"You don't need to have a serious, diagnosable depression to go talk to someone," she said. "If you feel down or if you feel like you're not yourself, go talk to somebody about it."

The AP-mtvU poll found that 84 percent of students said they'd know where to turn for help if they were in serious emotional distress or thinking about hurting themselves. Most said they'd go first to friends or family. Twenty percent said they'd try school counseling.

That means it may be up to friends and family to guide students toward professional help where warranted, said Malmon.

Dr. Thomas Insel, director of the National Institute for Mental Health, said students need to understand that depression is "a very treatable illness." Campus counseling centers are a good resource, he said, although they're not all set up take care of serious mental illnesses.

"There should be somebody there who could at least assess this, and in some cases offer reassurance that 'I'm sure you'll feel better after exams are over,'" he said. Serious cases can be referred for treatment, he said — "and treatment works."

Nearly 10 percent of adults in U.S. are depressedDepressive disorders afflict an estimated 9.5 percent of adult Americans in a given year, or about 20.9 million people. The median age for onset is 30.

According to the mental health institute, the first step to getting appropriate treatment is to visit a doctor. Certain medications and medical conditions, such as viruses or a thyroid disorder, can cause the same symptoms as depression. If doctors rule out a medical cause, then they should conduct a psychological evaluation or refer the patient to a mental health professional.

The poll was conducted April 22 to May 4 by Edison Media Research. To protect privacy, the schools where the poll was conducted are not being identified, the students who responded were not asked for their names and people interviewed for this story were not part of the survey. The poll has a margin of sampling error of plus or minus 3 percentage points.

The TV network mtvU is operated by the MTV Networks division of Viacom and available at many colleges. MtvU's sponsorship of the poll is related to its mental-health campaign "Half of Us," which it runs with the Jed Foundation, a nonprofit group that works to reduce suicide among young people.

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